Answer:
unsolvable because the second equation is just -2.5 times the first equation.
Step-by-step explanation:
2x-6y=12 then 2x=12+6y x=6+3y
-5x+15y=-30
substitute x
-5(6+3y)+15y=-30
-30-15y+15y=-30
y=y
Answer:
a) 
D. 9.74
b) 
B. 74
Step-by-step explanation:
Part a
We have the following dataset given:
69 74 75 62 70 93 64 69 61 88 67 77 87 90 66 91 77 63 82 82 71 74 76 65 83
We can begin calculating the sample mean with the following formula:

And replacing we got:

Now we can calculate the sample deviation with the following formula:

And after replace we got:

Part b
For this case we need to sort the value on increasing way:
[1] 61 62 63 64 65 66 67 69 69 70 71 74 74 75 76 77 77 82 82 83 87 88 90 91 93
And the median would be the value in the position 13 and we got:

Answer:
Either one: the two line have a point in common, or infinite: they are the same line.
The answer should be C: 12
Answer:
The answer is 7 x + 3 =24 because its a problem solving